1. Field of the Invention
This invention relates to a method of controlling negative resistance in a circuit, and in particular, to a gate modulated bipolar transistor which functions as a three terminal negative resistance device.
2. Background of the Invention
Heretofore, most negative resistance devices have had only two terminals. These devices have been used in microwave oscillator circuits. However, such present devices have several disadvantages. One disadvantage is that the circuit must be designed around the particular value of the resistance of the two terminal device to be used in the circuit. A second disadvantage is that these present two terminal devices are limited to moderate power circuit applications since the magnitude of the resistances range from a few tens to a few hundreds of ohms. A third disadvantage of present day devices is that the magnitude of the negative resistance is susceptable to thermal instability and require complex circuitry for biasing the same.
An object of this invention is to provide a new and improved negative resistance which overcomes the deficiencies of prior art devices.
Another object of this invention is to provide a new and improved negative resistance device which includes means for controlling the magnitude of the negative resistance thereof.
A further object of this invention is to provide a three terminal negative resistance device wherein the magnitude of the negative resistance is controlled by the voltage impressed on a control electrode of the device.
A still further object of this invention is to provide geometrical design criteria for fabricating a three terminal negative resistance design for a particular circuit requirement.
Other objects of this invention will, in part, be obvious and will, in part, appear hereinafter.